Cardboard box having a childproof lock system



FIG. 1 is a left side perspective thereof;

FIGS. 2 and 3 are left and right side elevational views thereof, respectively;

FIGS. 4 and 5 are top and bottom plan views thereof, respectively;

FIGS. 6 and 7 are front and rear end elevational views thereof, respectively; and,

FIG. 8 is a bottom perspective view thereof. 

CLAIM The ornamental designs for “cardboard box having a childproof lock system,” as shown and described. 